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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

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238                                ALASKAN GLACIER STUDIES
THE VALDEZ GIACIEH -
General Description. The Valdez Glacier (Pis. XCIV, A, and XCV) is a through glacier whose northern terminus is called Klutena Glacier. It has been described by Schrader as follows.1 "Starting from Valdez, the trail leads 4 miles northeast, with a very gentle rise over the delta gravels, to the foot of the Valdez glacier, thence about north for 18 miles up the glacier to the summit, which is 4800 feet high. The glacier is broken or transversely marked by four or five successive long benches or terraces,, from one to the other of which the rise of 100 feet or more is usually sharp and sometimes difficult, the topography of the ice being rugged, with crevasses, ridges, and turrets. With the exception of these benches the ascent from the foot of the glacier to near the summit, is gradual; but just before reaching the top there is a steep rise of a thousand feet at an angle of 15 to 20. The pass is guarded by a couple of prominent, peaks, one on either side and standing about a mile apart. From the summit the trail descends rapidly, but nowhere abruptly, for a distance of 6 miles through a canyon-like valley to the foot of the Klutena glacier, which is the source of the Klutena. river."
Valdez Glacier trends a little west of north to the divide, Bates Pass, beyond which the other end of the through glacier bends eastward again. It averages two miles in width, while Klutena Glacier is from one to two miles wide. Omitting two barely detached tributary glaciers, Valdez Glacier receives two tributaries from the east and one from the west, while Klutena Glacier receives two eastern and one western tributary near Bates Pass. The latter, which has a width of about two miles, heads at least ten miles farther to the west on a 5000-foot pass, perhaps as a through glacier with the Shoup or Columbia ice tongues, and flows eastward and bifurcates near Summit Peaks, sending a smaller glacial distributary northeastward to Klutena Glacier and a larger one southeastward to Valdez Glacier.
The Bates Pass ice tongue is another through glacier east of this one (PL XCV), the divide being covered by a snowfield. The Klutena terminus is 2020 feet above sea level and from it a stream flows to Copper Eiver. The Valdez terminus is 210 feet above sea level, the difference in elevation of the termini being mainly a response to the difference in snowfall on the seaward and landward sides of the mountain range. The mountain walls of the Valdez-KIutena through glacier rise from four to over seven thousand feet, being much oversteepened by former glacial erosion. The glacier surface is made-up of a series of ice falls and gentler slopes so that the prospectors spoke of it as divided into "benches." There are no pronounced medial moraines, but the lateral moraines are broad, and near the terminus several faint medial moraines are disclosed by ablation.
The width of Valdez Glacier at the terminus is a mile and a quarter, or a mile and three-quarters around the slightly curved periphery of the front. The ice front rises-800 feet in the first quarter of a mile, and reaches an elevation of 1000 feet seven-eighths of a mile from the end, 1500 feet a mile and a hah* back, and 2750 feet at a distance of eleven and a half miles from the terminus.
A mile and a half from the end of the glacier, on the eastern side, is the valley of a detached tributary into which Valdez Glacier bulges slightly. The small glacier in this valley (which we have named Camicia Glacier) is three-eighths of a mile wide and
i Schrader, F. C., Report on Prince William Sound and the Copper River Region, in Maps and Descriptions of Routes of Exploration in Alaska in 1898, Special Publication, U. S. Geol. Survey, 1899, p. 61.